收稿日期: 2015-02-07
修回日期: 2015-03-27
网络出版日期: 2015-10-10
基金资助
国家自然科学基金项目(编号：41227901;41502294);中国科学院战略性先导科技专项B类项目（编号：XDB10030000； XDB10030300；XDB10050400）联合资助.
Numerical Modeling of Stress Shadow Effect on Hydraulic Fracturing
Received date: 2015-02-07
Revised date: 2015-03-27
Online published: 2015-10-10
从岩石的细观非均质特性出发，采用岩石破裂失稳的渗流—应力—损伤耦合分析系统，设计了一系列的数值试验揭示水力裂缝间的应力阴影效应。试验条件下的研究结果表明：①应力阴影效应受水平应力差系数、注入孔间距、岩石非均质性、压裂顺序的影响，表现为排斥和吸引2种力学行为，体现在裂缝尖端应力伞面积、裂缝宽度和长度方面；②随着岩石均质度的提高，应力阴影效应对尖端应力伞的影响变弱，裂缝尖端应力伞的面积逐渐减小；③水平应力差较小时，井孔间距对应力阴影效应的贡献要大于远场应力；高水平应力差时，远场应力对“Stress shadow”的影响要强于井孔间距；④应力阴影效应伴随着裂缝的动态扩展而不断变化，裂缝尖端的应力伞面积和缝长具有很强的相关性，二者服从幂函数分布。通过这一研究，可以为水平井多裂缝射孔间距优化提供一定的理论依据。
王宇，李晓，王金波，郑博，张搏，赵志恒 . 水力压裂中的应力阴影效应与数值计算[J]. 天然气地球科学, 2015 , 26(10) : 1941 -1950 . DOI: 10.11764/j.issn.1672-1926.2015.10.1941
From the aspect of meso-structure heterogeneity of gas shale,the seepage- stress-damage coupling code was used to investigate the stress shadow effect during hydraulic fracturing.The experimental results show that: (1)The stress shadow effect is affected by horizontal differential stress,injection spacing,heterogeneity and fracturing sequence.It displays repel and attract mechanical behaviors,which influences the stress-umbrella area,fracture length and width.(2)With the decrease of rock heterogeneity,the stress shadow effect has weaker influence on the stress-umbrella area,area becomes smaller gradually.(3)When the horizontal differential stress is smaller,influence of injection spacing on stress shadow competes over the far-field stress;with higher horizontal differential stress,influence of far-field stress on stress shadow competes injection spacing.(4)The stress shadow effect displays dynamic variation with the evolution of hydraulic fractures.There is strong correlation between stress umbrella area and fracture length,and they obeyed power function.Through this research,it can provide certain theatrical basis for horizontal well spacing and multiple perforation spacing optimization.
[1]King G E.Thirty Years of Gas Shale Fracturing:What Have We Learned[R].Paper SPE 133456 presented at the SPE Annual Technical Conference and Exhibition,Florence,Italy,2010.
[2]Sondergeld C H,Newsham K E,Comisky J,et al.PeterophysicalConsideration in Evaluating and Producing Shale Resources[R].SPE 131768,2010.
[3]Stress shadowing and microseismic Events:A numericalevolution[R].SPE 147363,2011.
[4]Warpinski N R,Teufel L W.Influence of Geologic Discontinuities on Hydraulic Fracture Propagation[R].JPT,1987:209-220.
[5]Warpinski N R,Branagan P T.Altered-stress Fracturing[R].SPE 17533,1989.
[6]Meyer B R,Bazan L W.A Discrete Fracture Network Model for Hydraulically Induced Fractures:Theory,Parametric And Case Studies[R].SPE paper 140514 presented at the SPE Hydraulic Fracturing Conference and Exhibition,Woodlands,TX,USA,1991.
[7]]Britt L K,Smith M B.Horizontal Well Completion,Stimulation Optimization,and Risk Mitigation[R].SPE 125526,2009.
[8]Cheng Y.Boundary Element Analysis of The Stress Distribution Around Multiple Fractures:Implications for the Spacing of Perforation Clusters of Hydraulically Fractured Horizontal Wells[R]//SPE 125769 presented at the SPE Eastern Regional Meeting,Charleston,West Virginia,2009.
[9]Roussel N P,Manchanda R,Sharma M M.Implications of Fracturing Pressure Data Recorded During A Horizontal Completion on Stage Spacing Design[R].SPE 152631,2012.
[10]Germanovich L N,Astakhov D K.Fracture closure in extension and mechanical interaction of parallel joints[J].Journal of Geophysical Research,2004,109(9):2208-2222.
[11]Olson J E.Multi-fracture Propagation Modeling:Applications to Hydraulic Fracturing in Shales and Tight Sands[R].42nd US Rock Mechanics Symposium and 2nd US-Canada Rock Mechanics Symposium,San Francisco,2008.
[12]Olson J E.Fracture Mechanics Analysis of Joints and Veins[D].PhD dissertation,Stanford University,San Francisco,1990.
[13]Yew C H,Mear M E,Chang C C,et al.On Perforating and Fracturing of Deviated Cased Wellbores[R].SPE 26514,1993.
[14]Nolte K.Fracturing pressure analysis for nonideal behavior[J].Journal of Petroleum Technology,1991,42(2):210-218.
[15]Fisher M K,Heinze J R,Harris C D,et al.Optimizing Horizontal Completion Techniques in the Barnett Shale Using Microseismic Fracture Mapping[R].SPE 90051,2004.
[16]Morrill J C,Miskimins J L.Optimizing Hydraulic Fracture Spacing in Unconventional Shales.Society of Petroleum Engineers[R].SPE 152595,2012.
[17]Daneshy A,Au-Yeung J,Thompson T,et al.Fracture Shadowing:A Direct Method for Determining of the Reach and Propagation Pattern of Hydraulic Fractures iIn Horizontal Wells[R].Society of Petroleum Engineers.SPE 151980,2012.
[18]Li L C,Tang C A,Li G,et al.Numerical simulation of 3d hydraulic fracturing based on an improved flow-stress-damage model and a parallel fem technique[J].Rock Mechanics and Rock Enginnering,2012,45(5):801-818.
[19]Tang C A,Tham L G,Lee P K K,et al.Coupled analysis of flow,stress and damage (FSD)in rock failure[J].International Journal of Mining Science and Technology,2002,39(4):477-489.
[20]Wang S Y,Sun L,Au ASK,et al.2D-numerical analysis of hydraulic fracturing in heterogeneous geo-materials[J].Construction and Building Materials,2009,23(6):2196-2206.
[21]Fang Z,Harrison J P.Development of a local degradation approach to the modeling of brittle fracture in heterogeneous rocks[J].International Journal of Rock Mechanics & Mining Sciences,2002,39(4):443-457.
[22]Renshaw C E,Pollard D D.Are large differential stresses required for straight fracture propagation paths[J].Journal of Structural Geology,1994,16(6):817-822.
[23]Olga Kresse,Weng X W,Hong G U,et al.Numerical modeling of hydraulic fractures interaction in complex naturally fractured formations[J].Rock Mechanics and Rock Engineering,2013,46(3):555-568.
/
| 〈 |
|
〉 |
甘公网安备 62010202000678号